Plasmapheresis is a procedure which facilitates the collection of plasma for commercial fractionation into Clotting Factor VIII (also known as AHF), albumin, and other plasma-based protein fractions. During conventional plasmapheresis, a unit of whole blood is collected and separated into red blood cells and plasma. The red blood cells are returned to the donor, and the plasma is retained for fractionation purposes. Another unit of whole blood is then drawn from the same donor and again separated into red blood cells and plasma. Again, the red blood cells are returned to the donor, and only the plasma is retained.
Thus, two units of plasma can be obtained from a donor during a conventional plasmapheresis procedure. The two units of plasma are typically collected, or pooled, in a single container which has been specially designed for this purpose. The pooled plasma is frozen in the container and shipped to a fractionation facility. At the facility, the plasma is thawed and dumped from the container into a vat for fractionation.
A prior art plasma pooling container 1Oa is shown in FIG. 1. This container 1Oa is similar to one manufactured and sold by the Fenwal Division of Travenol Laboratories, Inc. (Deerfield, Illinois) as the PLASMA-GARD.TM. Plasma Pooling Bottle. The container lOa is manufactured from thermoplastic resins and includes an integral cap 12a and a narrow, constricted neck 14a. Plasma is transferred into the container 1Oa by use of a transfer set 16a having, at one end, a pointed spike 18a which is driven by the user through the cap 12a. To enable fluid transfer, a vent tube 20a is also driven by the user through the cap 12a. A pair of spikes 22a is situated at the other end of the transfer set 16a. Each spike 22a pierces a rupturable diaphragm 1ocated in the port of a bag (not shown) in which a unit of whole blood is collected and centrifugally separated into red blood cells and plasma. After the plasma of two collection bags has been pooled in the container 10a, the narrow, constricted neck 14a is cut generally along the line 24a to separate the cap 12a. At the same time, the neck 14a is sealed closed along the cutting line 24a by special heat sealing equipment to provide an air and fluid-tight seal for the container 10a.
A similar prior art pooling container (not shown) is disclosed in Shine et al U.S. Pat. No. 3,957,168. See also Shine et al U.S. Pat. No. Des. 255,872.
Another prior art plasma pooling container 10b is shown in FIG. 2. This container 10b is similar to one manufactured and sold by Alpha Therapeutic Corporation (South Pasadena, California) and is generally disclosed in Safianoff U.S. Pat. No. 4,234,095. Like the container 10a just described, the container 10b is manufactured from a thermoplastic material and includes an integral cap 12b. Unlike the cap 12a, the cap 12b includes preformed sleeves 26 each of which defines a target for placement of the spike 18b associated with the plasma transfer set 16b. Each sleeve 26 also includes a preformed cylindrical guide 28 (shown in phantom lines in FIG. 2) which retains the inserted spike 18b in a tight interference fit. Also unlike the cap 12a, the cap 12b includes an integrally formed vent tube 30b. In this arrangement, after the plasma is pooled in the container 10b, the container 10b is closed by sealing and severing the tubing of th.e attached plasma transfer set 16b generally along the line 24b.
The resulting seal is fluid-tight. However, unlike the container 10a, the container 10b is not hermetically sealed, because the vent tube 30b is never closed. To maintain sterility in this arrangement, the vent tube 30b includes a plug 32b of sterile fibrous material.
Yet another prior art plasma pooling container 10c is shown in FIG. 3. This pooling container 10c is similar to one manufactured and sold by Terumo Corporation (Japan) as the PLASMAFLEX.TM. Pooling Bottle. This container 10c is also manufactured from a thermoplastic material and includes an integral cap 12c. An end of the transfer set 16c is integrally connected to one port 34 in the cap 12c, thereby eliminating the need for a spike. A vent tube 30c with a bacterial filter 32c (shown in phantom lines in FIG. 3) is provided in communication with another port 35 on the cap 12c. In this arrangement, the upper portion of the tubing is held relatively stationary by a holder 36. After the plasma has been collected, the upper portion tubing of the transfer set 16c is heat sealed closed and severed generally along the line 24c.
As with the bottle 10b, the resulting seal of the container 10c is fluid-tight , but it is not hermetic, because the vent tube 30c remains open.
Because the container 10b and 10c are not completely hermetically sealed, quick and efficient water bath immersion techniques cannot be used to thaw the plasma. Rather, more time-consuming techniques, such as shelf thawing or batch thawing, have to be utilized.
Furthermore, in both of the containers 10b and 10c, the sealed ends 24b and 24c of the associated transfer sets 16b and 16c are exposed to contact throughout freezing, shipping, and thawing operations. This tubing (typically made from a plasticized polyvinyl chloride material) can become brittle during exposure to low temperatures and can thus become even more vulnerable to being inadvertently broken or damaged as a result of contact. Should this occur, the sterile integrity of the frozen contents of the bottle 10b or 10c is, of course, compromised.
With the foregoing considerations in mind, one of the principal objects of the invention is to provide a plasma pooling container or the like which serves to shield or protect the sealed end portion of associated tubing from being inadvertently broken or damaged during handling, thereby assuring that the sterile integrity of its contents is not compromised.
Another principal object of this invention is to provide a plasma pooling container or the like which can be hermetically sealed, thereby allowing complete water bath immersion of the container, if desired.